The invention relates to a strand guiding roller with at least one roller shell and with at least two supporting shafts, two supporting shafts being respectively connected in a rotationally fixed manner to a roller shell and each supporting shaft being rotatably supported in a supporting bearing.
A strand guiding roller of this type is already known from DE-A 24 23 224. In the case of this multi-part strand guiding roller, roller shells neighboring one another in the axial direction are connected by a supporting shaft which is rotatably supported in a journal bearing and engages with shaft stubs directed away from one another in axial recesses of the neighboring roller shells. A non-positive connection between the supporting shaft and the respective roller shell takes place by means of a screw connection between the two components and by interacting radial supporting surfaces on the supporting shaft and on the roller shell, whereby additional securement against release during operation of the plant is achieved. However, this design solution has not proven successful in practice, since this way of holding the components together does not withstand the rigours of metallurgical plant operation.
It is already known from WO 02/02253 A1 to form driver rollers in a strip casting plant from a roller shell and two supporting shafts, wherein the two supporting shafts, lying opposite one another, protrude into the roller shell and are screwed at their extreme ends to the roller shell (FIG. 6). The tightening screws are at the same time used as closure elements of the coolant lines.
A one-part strand guiding roller in which a roller shell is undetachably connected to two supporting shafts by a peripheral welded connection is known from DE-A 28 40 902. The roller shell is coated with an abrasion-resistant, non-corroding protective layer. Damage to individual components of a strand guiding roller usually result in their total loss and in high spare part costs.
The use of a weld for the connection of the roller shell and the supporting shaft is specifically not practicable for multi-part strand guiding rollers, since split bearings should necessarily be used for these. Such a centrally mounted strand guiding roller, in which a supporting shaft carrying a supporting bearing is connected to adjoining roller shells by welded connections is known from DE-A 32 28 190.
In the case of conventional peripherally cooled strand guiding rollers, as are already known for example from EP 0 543 531 A1 or AT 412 851 B, the coolant is conducted through coolant channels predominantly arranged radially or inclined in relation to the axis of rotation of the roller from the center of the roller to the periphery of the strand guiding roller, distributed there by way of ring lines, taken close to the surface of the roller shell through coolant channels aligned parallel to the roller axis and in an analogous way collected again and returned to the center. To make it easy to produce the coolant conducting system and the ring lines and seal them tightly with respect to the outside, sealing elements in the form of rings or plugs are usually screwed or welded to the end faces of the roller shell. Owing to the high thermal and material-related loads in the strand guiding roller, these sealing methods are complex, very sensitive and susceptible to faults.
It is also known in the case of strand guiding rollers with a continuous core shaft to fasten multi-layered roller shells in a rotationally fixed and detachable manner on the core shaft, for example by a feather key connection. The multi-layered structure of the roller shell is obtained by individual cylindrical sleeves, which are connected in a rotationally fixed manner by a full-area shrink-fit connection of the lateral surfaces of the cylinders lying opposite one another. The easy-to-produce coolant channels are located at the contact surfaces of the cylindrical sleeves (WO 2005/016578; WO 02/02253).